Many of today's electronic systems are portable and provide users with mobility and ease of transport. Laptops, cellular phones, digital cameras, portable gaming systems, handheld GPS receivers, are just a few examples of portable electronic systems. These systems generally have become increasingly lighter and smaller in form factor, while at the same time, however, these systems may have ever greater performance than their predecessors. The increased performance typically has come at the expense of greater power consumption. Since these systems rely on battery power, system designers make an effort to design systems for low power consumption so that the systems can be operated for a greater length of time before replacing or recharging the battery.
As part of the effort to design lower power electronic systems, system designers often design electronic systems to utilize components and circuitry that operate with lower power consumption. For example, since many of today's systems include memory devices for storing data that are used during operation, using lower power memory devices may result in a significant reduction in the overall power consumed by such systems. However, since greater memory capacity or performance may come at the cost of additional power consumption, there may be a tradeoff between operating at lower power while maintaining or improving performance.
Significant power may also be consumed by electronic systems in coupling signals within individual components and between different components since substantial power may be consumed in signal lines through which signals are coupled. Significant power may also be consumed in transmitting and receiving circuits for the signals. In general, the amount of power consumed is somewhat proportional to the magnitude of the signals being transmitted and received. Thus, reducing the magnitude of the signals being coupled may reduce the amount of power consumed. However, reducing the magnitude of signals transmitted and received within a component and between components can result in a variety of other problems. Thus, there may be a practical limit in the degree to which power in electronic systems may be reduced, although improvements continue to reduce the value of this practical limit.